A pipe friction experiment for air consists of a smooth brass tube with \(63.5 \mathrm{~mm}\) inside diameter; the distance between pressure taps is \(1.52 \mathrm{~m}\). The pressure drop is indicated by a manometer filled with Meriam red oil. The centerline velocity \(U\) is measured with a pitot cylinder. At one flow condition, \(U=23.1 \mathrm{~m} / \mathrm{s}\) and the pressure drop is \(12.3 \mathrm{~mm}\) of oil. For this condition, evaluate the Reynolds number based on average flow velocity. Calculate the friction factor and compare with the value obtained from Eq. 8.37 (use \(n=7\) in the power-law velocity profile).